diff --git a/lib/websocket/extensions/parser.rb b/lib/websocket/extensions/parser.rb
index d2434df..f8d8891 100644
--- a/lib/websocket/extensions/parser.rb
+++ b/lib/websocket/extensions/parser.rb
@@ -6,7 +6,7 @@ class Extensions
     class Parser
       TOKEN    = /([!#\$%&'\*\+\-\.\^_`\|~0-9A-Za-z]+)/
       NOTOKEN  = /([^!#\$%&'\*\+\-\.\^_`\|~0-9A-Za-z])/
-      QUOTED   = /"((?:\\[\x00-\x7f]|[^\x00-\x08\x0a-\x1f\x7f"])*)"/
+      QUOTED   = /"((?:\\[\x00-\x7f]|[^\x00-\x08\x0a-\x1f\x7f"\\])*)"/
       PARAM    = %r{#{ TOKEN.source }(?:=(?:#{ TOKEN.source }|#{ QUOTED.source }))?}
       EXT      = %r{#{ TOKEN.source }(?: *; *#{ PARAM.source })*}
       EXT_LIST = %r{^#{ EXT.source }(?: *, *#{ EXT.source })*$}
diff --git a/spec/websocket/extensions/parser_spec.rb b/spec/websocket/extensions/parser_spec.rb
index ec3a837..7458210 100644
--- a/spec/websocket/extensions/parser_spec.rb
+++ b/spec/websocket/extensions/parser_spec.rb
@@ -76,6 +76,12 @@ def parse(string)
         { :name => "a", :params => { "b" => true } }
       ]
     end
+
+    it "rejects a string missing its closing quote" do
+      expect {
+        parse "foo; bar=\"fooa\\a\\a\\a\\a\\a\\a\\a\\a\\a\\a\\a\\a\\a\\a\\a\\a\\a\\a\\a\\a\\a\\a\\a\\a\\a\\a\\a\\a\\a\\a"
+      }.to raise_error(WebSocket::Extensions::Parser::ParseError)
+    end
   end
 
   describe :serialize_params do